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If you think life on earth is stressful, try spending time in space. You must constantly perform high-profile tasks with experts critiquing every move. You don’t have your family and friends around to support you. You have unnatural light, zero gravity, strange food, and disrupted sleeping patterns. Astronauts are isolated, fatigued, and STRESSED. How does this affect their health?

Twins and Telomeres

Scientists are working on data from an interesting study that involves identical twin astronauts. Mark and Scott Kelly are the subjects of a NASA study that highlights what happens to someone in space. Mark and Scott, identical twins, were selected as Space Shuttle pilots in 1996. Mark has spent over 54 days in space, but he stayed here on Earth while Scott spent nearly a year (340 days) on the International Space Station. Before Scott left, he and Mark went through a battery of tests that compared their identical genes and DNA so that scientists could see what happens to the human body in space. Besides being two inches taller when he returned, Scott also had an increase in methylation, the process that turns genes on and off. Scientists said that Scott’s genes “exploded like fireworks” in space, with thousands of genes turning on and off.

One fascinating preliminary finding is that Scott’s telomeres got longer in space, but shortened when he returned—exactly the opposite of what scientists thought would happen. In another interesting twist, after Scott returned to Earth, he and Mark both experienced the same stressful family event—and their telomeres shortened. As discussed in Biohacking the Aging Code: How to Increase Your Healthy Years, scientists think there is a link between telomere length, stress, and aging. Did Scott’s telomeres lengthen while he was in space because of his increased exercise and reduced caloric intake? Or is there another reason that being in space affects telomere length? Scientists are still investigating and are hoping to publish final results sometime this year.

Mice and Nrf2

In the meantime, Japanese astronaut Norishige Kanai is spending six months on the International Space Station performing experiments that look into “space stress“. He will be comparing two sets of mouse bones—one set that he took into space and one set that will remain on earth. He’ll examine how cosmic rays and weightlessness affect the bones that go into space. Kanai will also raise two types of mice on the International Space Station—one group will be bred to have the Nrf2 protein, the other group will not. Kanai and other researchers believe that Nrf2 protein, which provides antioxidant defenses, will reduce the effects of “space stress.” When the mice return to Earth, scientists will see if the different types of mice responded to space differently.

Kanai’s findings combined with the findings of the twin study will raise some interesting questions. Does Nrf2 create antioxidants that help mice—and potentially humans—deal with stresses that affect telomere length or other types of damage to genes that can occur in space? How can we use this knowledge here on Earth to minimize the damage caused by stressors? Stay tuned to find out!